class UserInfo(object):
    __start = 0;

    def __init__(self):
        self.phone_no = '18900000003'
        self.password = 'abcd1234'

    def generate_one(self):
        return self

    @staticmethod
    def generate_mobile_no(start_phone_no = None):
        mobile_start_from = '18300000000'
        if start_phone_no is None:
            if hasattr(UserInfo, '__start_phone_no'):
                if UserInfo.__start_phone_no is None:
                    UserInfo.__start_phone_no = mobile_start_from
            else:
                UserInfo.__start_phone_no = mobile_start_from
        else:
            UserInfo.__start_phone_no = start_phone_no
        UserInfo.__start += 1
        result = int(UserInfo.__start_phone_no) + UserInfo.__start
        return result
